12V Test Point - THOMSON 50M14DP Service Manual

3.14 24V‐12V test point
The IC used for 24V‐12V is TI's TPS54331.It is also used in MT32,MT10B. It is also a
BUCK reduction voltage just like MP1593.It sets output voltage by using resistance to
separate voltage sampling.PIN4 is Soft start.PIN3 is Enable and is high level in
order.PIN6 is Compensator.PIN5 is Feedback voltage and is 0.8V in usally.PIN1 is
Bootstrap connecting to a freewheeling diode's negative pole with a
capacitance.PIN8 is inner MOS push‐pull outputs to freewheeling diode's negative
pole connecting with energy storage inductance. Inner MOS will give energy to
inductance and supply voltage to load when it is break‐over. Inductance release
energy by freewheeling diode so as to reduce voltage when inner MOS is cut‐off.
Vout=0.8*(1+R104/R105)
9
L101 is the test point of
24V‐12V.